Brown practices with Raiders

Star receiver Antonio Brown practiced in a certified helmet with the Oakland Raiders on Tuesday, two days after being given an ultimatum by general manager Mike Mayock to be "all in or all out."

Brown didn't attend practice Sunday as he worked to find a helmet he was comfortable using and that met safety standards set by the NFL and NFLPA. He lost a grievance last week in which he sought to be allowed to use the Schutt Air Advantage helmet he has worn throughout his career. But the helmet was too old to be certified as safe.

He had hoped to find a newer version of his preferred helmet that could be approved but the one he submitted failed a safety test conducted by the league and union.

He filed a second grievance Monday seeking a one-year grace period, according to a person familiar with the situation who spoke on condition of anonymity because it wasn't made public. But he is back practicing with the team while that gets resolved.

Bills: Starting center Mitch Morse has been allowed to practice, a move that puts him one step closer to being cleared from the NFL's concussion protocol.

Cowboys: Agreed on a $64 million, five-year contract extension with young linebacker Jaylon Smith. The 24-year-old Smith's contract, which includes $35.5 million in guaranteed money, was announced Tuesday. ... Star running back Ezekiel Elliott won't face criminal charges after scuffling with a music festival security guard in Las Vegas.

Jets: Claimed safety Derrick Kindred off waivers from the Colts.

Patriots: Cut punter Ryan Allen, who booted them to three Super Bowl victories in six seasons. First signed as an undrafted free agent in 2013, the left-footer punted 409 times. He had five punts, putting three of them inside the 20-yard line, in February's Super Bowl victory over the Los Angeles Rams.